Gulf dredging raises questions about red tide and beach conditions

The beaches of Southwest Florida are a major attraction and a key reason why many visit or move to the area. But with hurricanes and natural beach erosion, sand renourishment is often necessary.

But could the process of fixing our beaches do more harm than good?

10 miles off Sanibel, a sand dredging project is underway. Next to sand sediments kicked up from dredging, the Gulf is stained with orangish streaks of red tide.

This is not dredging for Sanibel beaches. Sanibel trucks in sand from a mine in Moore Haven to replenish its beaches.

In Collier County, Park Shore Beach sources its sand from a mine in Immokalee.

Fort Myers Beach started its renourishment before Thanksgiving. The town started work on the South end in early February and hope to have all projects done in March.

“For tourism, it’s huge. It’s our main industry in Florida. So we want to keep our beaches in good shape. You know, sand is always moving around and getting we will. You can see some parts of the beach where there’s basically no more beach,” said Chadd Chustz, environmental manager for the Town of Fort Myers Beach.

But it’s more than maintenance, “also for the wildlife, if there’s no sand and then there’s no nesting habitat, and makes them difficult to recover from their threatened status,” added Chustz.

The sand used to replenish Fort Myers Beach is dredged 1.5 miles off the island.

10 miles off Sanibel, is another dredging project for Lee County Beaches. While sand is dredged in the Gulf, red tide is running rampant.

The question has been raised, what is their relationship?

“Dredging can cause some direct and indirect effects. So when you’re dredging up the bottom sediments, that re-suspends nutrients and potential other pollutants that are in that layer down there on the bottom,” said John Cassani, Calusa Waterkeeper emeritus.

Red tide is one of Southwest Florida’s original settlers, it’s natural but, “The frequency, duration, and severity that we’re seeing now in recent decades, is not natural,” said Cassani.

Mike Parsons, a professor of marine science at Florida Gulf Coast University, has a different perspective on sand dredging and red tide.

“There probably is not a strong relationship between the dredging and the blooms. The sediments can be a source of nutrients to feed red tide, but usually, sand doesn’t have that much nutrients in it,” Parsons said.

But Parsons notes, there’s still a lot we don’t know.

“It’s something that’s under studied, and it’s something that we probably need to get better numbers on so it’s possible, but I don’t, I don’t think in this case, because, you know, the hurricanes really mixed a lot of things up,” Parsons added.

While we may not yet fully understand the relationship between red tide and dredging we know their relationships with our economy and tourism.

Without the beaches, tourism drops, and with red tide on the beaches, tourism drops as well.